The invention relates to flexible channel-section strips for use as draught excluding seals, beadings, flange finishers (for covering welded flanges) and the like, particularly though not exclusively for use in vehicle construction. Such strips are hereinafter referred to generically as "sealing strips" or "channel-shaped sealing strips". More especially, the invention relates to sealing strips to the outside of one of the channel walls of which is attached a length of beading of soft material, such as rubber material in tubular form.
Channel-shaped sealing strips are known in which a channel-shaped metal core or carrier is provided with a complete coating of a relatively hard flexible material such as plastics. Such a sealing strip may be fitted over a flange around a door or window opening, such as in a motor vehicle body, and protects and hides the flange. In many applications, however, it is desired that the sealing strip shall also provide a draught and weatherproofing function, and it is known to secure a beading of relatively softer material to the outside of one side wall of the sealing strip. The sealing strip is mounted onto the flange so that the door closes onto this soft beading to provide the desired draught and weatherproofing. However, such a construction is wasteful of expensive material since one side of the channel is, of necessity, covered by a layer of plastics material and also by a layer of the softer material forming the beading. Additionally, there is the problem of securing the softer sealing section to the relatively hard material. Such securing may be carried out by means of stitching or adhesive or some form of mechanical interlock. In any of these cases, however, it is expensive of time and/or material, and/or introduces production difficulties.
It is an object of the invention to provide an improved channel-shaped sealing strip.
It is a more specific object of the invention to provide a channel-shaped sealing strip with an improved mounting for the sealing beading, and an improved method for making such a sealing strip.
Channel-shaped sealing strips may be provided with gripping ribs running along the inside, facing, walls of the channel and projecting towards each other for assisting in maintaining the strip on a mounting flange. It is another object of the invention to provide a channel-shaped sealing strip with improved and more efficient gripping ribs.